Subtle and asymptomatic nature of high blood pressure results in increase in mortality and morbidity. Dentists may play a vital role in identifying patients with suspected hypertension who are not yet diagnosed to refer them timely to physicians for diagnosis and management of the condition. The aim of this study was to compare the oral health status using decayed, missing, filled teeth (DMFT) index and perceived stress score using perceived stress scale (PSS-10) between systemically healthy dental patients, and patients with undiagnosed and known hypertension attending dental out-patient department of Combined Military Hospital (CMH) Lahore Medical College & Institute of Dentistry, Lahore, Pakistan. It is a cross-sectional descriptive study in which 108 patients participated selected through purposive sampling method, 36 in each group. According to Kruskal Wallis H test, there were significant associations seen among the three groups with age (p < 0.001), DMFT (p < 0.001), and PSS-10 scores (p = 0.003). According to Spearman’s matrix correlations, moderate positive correlations were observed between mean arterial pressure (MAP) and DMFT (r = 0.46, p < 0.001), and MAP and age (r = 0.38, p = 0.001), DMFT and PSS-10 (r = 0.47, p < 0.001), and DMFT and age (r = 0.33, p = 0.004) in healthy and patients with undiagnosed hypertension. It may be concluded that patients with raised blood pressure have higher perceived stress and deteriorated oral health.